Air Handling Unit That Eliminates Corner Singularities and Eddies for High Energy Efficiency and Its Evaporator Heat Exchanger Coil Arrangements

ABSTRACT

An air handling unit with a cross-sectional profile of continuous curvature eliminates corner singularities and eddies for high energy efficiency in comparison to rectangular air handling units. A housing has an outer shell, an inner shell, and an insulation shell between the outer and inner shells. A blower and motor assembly forces air through an air intake opening over a heat exchanger, and out through an air discharge opening. An upper door and a lower door in the wall of the housing allow maintenance access to the blower and motor assembly and the heat exchanger. Three heat exchanger coil arrangements are also disclosed: an A-coil arrangement, a parallel coil arrangement, and a circular coil arrangement.

The current application claims a priority to the U.S. Provisional Patent application Ser. No. 62/054,584 filed on Sep. 24, 2014.

FIELD OF THE INVENTION

The present invention relates generally to air handling. More particularly, the present invention relates to central air conditioners and heat pumps.

BACKGROUND OF THE INVENTION

An air handling unit of any central air conditioner and heat pump or similar systems is a chamber that encloses devices that generate, control and circulates conditioned air throughout a building or structure where the system is installed. The air conditioning process provides the desirable cooling, dehumidifying, heating, air quality and comfortable environment within the building or structure. The energy efficiency of such a central air conditioning system depends largely on the level of efficiency of each device, such as the heat exchanger, the blower fan and motor assembly; and the air filter within an air handling unit of the system. The control of airflow characteristics within the air handling unit by suppressing corner flow singularities and eddies, thereby preventing loss of energy through dissipation also enhances the system energy efficiency, and is the object of the present invention.

In heating, ventilation, and air conditioning (HVAC) systems, energy efficiency of air conditioners measures the difference between how much energy is used to provide the same level of comfort by the same type of products and is often referred to as Energy Efficiency Ratio (EER) defined as the product's cooling output in BTUs per hour divided by its consumption of electric energy measured in watts. In the HVAC industry, however, Seasonal Energy Efficiency Ratio (SEER) is often preferred to describe energy efficiency of air conditioners. The SEER is defined as the cooling output during a typical cooling season divided by the total electric energy input during the same period.

While optimization of devices within an air handling unit improves performance, the design leveraging a shape of continuous curvature such as circular or cylindrical system of the present invention increases the efficiency. Most air handlers for central air conditioning and heat pump systems on the market today are rectangular and none are a shape of continuous curvature such as a circular or cylindrical shape. The rectangular air handling units are subject to corner flow singularities and eddies resulting in energy dissipation in form of heat within the chamber. However, the dissipated or lost energy must be replenished if the air flow rate in the chamber is to be maintained, in the same way, as energy must be provided to overcome friction. The supply of more energy by the blower motor to accomplish the desired airflow rate will result in a decrease in the efficiency of the air conditioning system. In the present invention the air handling unit with a shape of continuous curvature such as a circular or cylindrical shape circumvents the problem of corner singularities and eddies for higher energy efficiency from energy savings due to reduction in blower motor power consumption.

To authenticate the object of the present invention, a numerical and laser interferometric analysis was used to obtain numerical and interferometric flow distributions in rectangular and circular air handling units.

The governing differential equations of the flow in both the rectangular and cylindrical coordinates are developed and transformed below into stream function and voracity formulations to enable visualization of theoretical flow distribution in the non-circular heat exchanger and circular heat exchanger of continuous curvature:

To authenticate the object of the present invention, a numerical and laser interferometric analysis was used to obtain numerical and interferometric flow distributions in rectangular and circular air handling units.

The governing differential equations of the flow in both the rectangular and cylindrical co-ordinates are developed and transformed below into stream function and voracity formulations to enable visualization of theoretical flow distribution in the non-circular heat exchanger and circular heat exchanger of continuous curvature:

Rectangular Coordinate:

Stream Function Equation:

${\frac{\partial^{2}\psi}{\partial x^{*2}} + \frac{\partial^{2}\psi}{\partial y^{*2}}} = {- \omega}$

Vorticity Equation:

${{\frac{\partial\psi}{\partial y^{*}}\frac{\partial\omega}{\partial x^{*}}} - {\frac{\partial\psi}{\partial x^{*}}\frac{\partial\omega}{\partial y^{*}}}} = {{\frac{Gr}{{Re}_{w}^{2}}\left( {{\sin \; \alpha \; \frac{\partial\theta}{\partial x^{*}}} + {\cos \; \alpha \frac{\partial\theta}{\partial y^{*}}}} \right)} + {\frac{1}{{Re}_{w}}\left( {\frac{\partial^{2}\omega}{\partial x^{*2}} + \frac{\partial^{2}\omega}{\partial y^{*2}}} \right)}}$

Cyclindrical Coordinate:

Stream Function Equation:

${\frac{\partial^{2}\psi}{\partial r^{2}} + {\frac{1}{r}\frac{\partial\psi}{\partial r}} + {\frac{1}{r^{2}}\frac{\partial^{2}\psi}{\partial\theta^{2}}}} = {- \omega}$

Vorticity Equation:

${{v_{r}\frac{\partial\omega}{\partial r}} + {\frac{v_{\theta}}{r}\frac{\partial\omega}{\partial\theta}}} = {{\frac{Gr}{{Re}_{w}^{2}}\left\lbrack {{{- \frac{\partial\theta}{\partial r}}\sin \; \left( {\theta + \alpha} \right)} - {\frac{1}{r}\; \frac{\partial\theta}{\partial r}{\cos \left( {\theta + \alpha} \right)}}} \right\rbrack} + \; {\frac{1}{{Re}_{w}}\left( {\frac{\partial^{2}\omega}{\partial r^{2}} + {\frac{1}{r}\frac{\partial\omega}{\partial r}} + {\frac{1}{r^{2}}\frac{\partial^{2}\omega}{\partial\theta^{2}}}} \right)}}$

Where

$\phi = \frac{k}{\rho \; c_{\rho}}$ ${G\; r_{w}} = \frac{{g\; \beta \; w^{3}T_{w}} - T_{\infty}}{v^{2}}$ ${Re}_{w} = \frac{u_{m} \cdot w}{v}$ $\theta = \frac{T - T_{\infty}}{T_{w} - T_{\infty}}$ $\Pr = \frac{v}{\phi}$ $u^{*} = \frac{\partial\psi}{\partial y^{*}}$ $v^{*} = {- \frac{\partial\psi}{\partial x^{*}}}$ $\omega = {\frac{\partial v^{*}}{\partial x^{*}} - \frac{\partial u^{*}}{\partial y^{*}}}$ $x^{*} = \frac{x}{W}$ $y^{*} = \frac{y}{W}$ $u^{*} = \frac{u}{u_{m}}$ $v^{*} = \frac{v}{u_{m}}$

x⁸, y⁸ are non-dimensional coordinates; r, θ are non-dimensional polar coordinates. u⁸, v⁸ are non-dimensional Cartesian coordinates; v_(r), v_(g) velocity polar coordinates; α=0. T=temperature.

The stream function voracity formulations discussed above are discretized and numerically solved at nodal points of the rectangular and cylindrical flow mesh systems. The simulation data at the nodal points are plotted to form the contours of the stream function showing the flow distributions or flow patterns in the rectangular and circular or cylindrical heat exchangers. The flow distributions or flow patterns reveal the presence of corner flow singularities and eddy in the rectangular shaped air handling unit which cause energy dissipation. Such corner flow singularities and eddies do not exist in the circular or cylindrical air handler of the present invention. In the circular air handler, however, there are weak concentric flow recirculation or eddies. However, the numerical and hotwire smoke visualization methods used here revealed that the flow eddies are further weakened toward the center and suppressed by the heat exchanger installed in the core region of the circular or cylindrical air handling unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevated perspective view of the present invention showing the closed upper and lower doors.

FIG. 2 is an elevated perspective view of the A-coil arrangement of the present invention in an open configuration excluding the upper and lower doors and showing the hidden air filter and air intake opening.

FIG. 3 is a front view of the A-coil arrangement of the present invention in the open configuration.

FIG. 4 is a right side sectional view along section A-A of FIG. 3.

FIG. 5 is a top sectional view along section B-B of FIG. 3.

FIG. 6 is a bottom sectional view along section C-C of FIG. 3.

FIG. 7 is an elevated perspective view of the parallel coil arrangement of the present invention.

FIG. 8 is a front view of the parallel coil arrangement of the present invention.

FIG. 9 is a right side sectional view along section D-D of FIG. 8.

FIG. 10 is an elevated perspective view of the circular coil arrangement of the present invention.

FIG. 11 is a front view of the circular coil arrangement of the present invention.

FIG. 12 is a right side sectional view along section E-E of FIG. 11.

FIG. 13 is an inferogram of flow distributions in a rectangular shaped heat exchanger showing corner flow singularities and eddies.

FIG. 14 shows a numerical simulation of flow distributions in a rectangular shaped heat exchanger showing corner flow singularities and eddies.

FIG. 15 is an inferogram of flow distributions in a circular shaped heat exchanger showing weak concentric flow recirculation in the core region but no corner flow singularities.

FIG. 16 shows a numerical simulation of flow distributions in a circular shaped heat exchanger showing weak concentric flow recirculation in the core region but no corner flow singularities.

DETAIL DESCRIPTIONS OF THE INVENTION

All illustrations of the drawings are for the purpose of describing selected versions of the present invention and are not intended to limit the scope of the present invention. The present invention is to be described in detail and is provided in a manner that establishes a thorough understanding of the present invention. There may be aspects of the present invention that may be practiced without the implementation of some features as they are described. It should be understood that some details have not been described in detail in order to not unnecessarily obscure focus of the invention.

The present invention is an air handling unit 1, which is a major component of a split system central air conditioning or heat pump, and its functions include generating, controlling and circulating conditioned air through a transport and distribution system to the building or structure where the unit operates in conjunction with an outdoor condensing unit. The air handling unit 1 of the present invention has a shape of continuous curvature such as a circular or cylindrical shape.

The cylindrical profile with continuous curvature of the air handling unit 1 (AHU) is the primary unique aspect of the present invention which distinctively differentiates its features, arrangement and performance from the commonly used rectangular air handlers for split systems central air conditioning and heat pump in HVAC industry. Notably, the cylindrical air handling unit 1 of the present invention has no corners, therefore, not susceptible to corner flow singularities and eddies which are the shortcomings of rectangular air handlers, thereby increasing energy usage efficiency. Additionally, several heat exchanger coil arrangements are disclosed as a secondary consideration in the present invention.

Referring to FIGS. 1-3, the preferred embodiment of the present invention comprises a housing 2, an air intake opening 3, an air filter 4, a heat exchanger 5, a blower and motor assembly 6, and an air discharge opening 7.

The housing 2 is the primary feature of the present invention, in that a cross-sectional profile 20 of the housing 2 is of continuous curvature. More particularly, the cross-sectional profile 20 is circular, making the housing 2 cylindrical. It should be understood that other cross-sectional profile 20s of continuous curvature may be comprised for the housing 2, such as, but not limited to, elliptical or other profiles with continuous curvature. The circular cross-sectional profile 20 serves to eliminate corner eddies and singularities within the housing 2, resulting in much improved energy efficiency in operating the air handling unit 1. The housing 2 of the air handling unit 1 of the present invention preferably has a greater height than width; however, this is not a required feature and the height of the housing 2 may be equal to or less than the width of the housing 2, depending on the specific implementation or requirements for a desired application.

In the preferred embodiment of the present invention, the housing 2 comprises an outer shell 21, an inner shell 22, and an insulation shell 23 as shown in FIG. 4. The outer shell 21 is concentrically positioned around the inner shell 22, and the insulation shell 23 is concentrically positioned between the outer shell 21 and the inner shell 22. Preferably, the inner shell 22 is non-corrosive or corrosion resistant in addition to being galvanized.

Additionally in the preferred embodiment, the housing 2 comprises a top end 24 and a bottom end 25, which are positioned vertically opposite each other along a central axis 26 of the housing 2, wherein the central axis 26 is defined to be oriented vertically for reference in the present disclosure. The air intake opening 3 traverses through the housing 2 at the bottom end 25, as shown in FIGS. 2 and 6. More particularly, the air intake opening 3 traverses through the bottom end 25 of the housing 2 and is positioned concentric to the housing 2.

Similarly, the air discharge opening 7 traverses through the housing 2 at the top end 24, and more particularly an outer top cover 8 is positioned concentric to the housing 2, and is connected to the top end 24 of the housing 2 as shown in FIGS. 1-5. An air discharge plenum 9 is also comprised in the present invention. The air discharge plenum 9 is adjacently connected to the top end 24 of the housing 2 and traverses through the top end 24 of the housing 2. More particularly, the air discharge plenum 9 traverses through the outer top cover 8, and the air discharge opening 7 traverses through the air discharge plenum 9.

In the preferred embodiment of the present invention, air flow through the housing 2 passes into the air intake opening 3, through the air filter 4, and out through the air discharge opening 7 in the air discharge plenum 9, passing generally vertically from the bottom end 25 to the top end 24. It is contemplated, however, that the air flow may be reversed from the aforementioned arrangement based on any desired implementation purposes, where the air flow is received into the air discharge opening 7, passes through the air filter 4 and is ejected through the air intake opening 3, passing generally vertically through the housing 2 from the top end 24 to the bottom end 25. While passing through the housing 2, the air flow additionally passes over and through the heat exchanger 5 and the blower and motor assembly 6, respectively. The air discharge plenum 9 protrudes upward from the housing 2, and a flange atop the air discharge plenum 9 opposite the housing 2 connects the present invention to air transport and distribution ducts for onward transfer of the conditioned air into the building, structure or space to be conditioned.

In the preferred embodiment of the present invention, the air filter 4 is positioned within the housing 2 adjacent to the air intake opening 3. It should be noted that the air intake opening 3, and thus the air filter 4, should not be restricted to be only positioned directly adjacent to the bottom end 25, but may be located in other positions in the housing 2 based on any desired implementation preference. It may be desirable for electrical components to be positioned adjacent to the bottom end 25, for example, necessitating the air filter 4 and air intake opening 3 to be moved upwards. Any suitable air filter 4 may be utilized, such as, but not limited to, commercially available or otherwise commonly known types of air filters, or an air filter 4 specifically designed to be compatible with or beneficial to the present invention.

In the preferred embodiment of the present invention, the air filter 4 is removable in order to facilitate maintenance of the air filter 4. To this end, the housing 2 further comprises a filter compartment 27 positioned within the housing 2 adjacent to the air intake opening 3; preferably, the filter compartment 27 is positioned vertically adjacent to the air intake opening 3, as the air intake opening 3 traverses through the bottom end 25 of the housing 2. The air filter 4 is removably positioned within the air filter 4 compartment 27, preferably through a filter slot laterally traversing into the housing 2 adjacent to the air filter 4 compartment 27. The filter may sit loosely within the air filter 4 compartment 27, or a filter pan may be removably positioned within the filter compartment 27 upon which the air filter 4 rests.

In the preferred embodiment of the present invention, the heat exchanger 5 and the blower and motor assembly 6 are positioned vertically adjacent to each other within the housing 2. This arrangement facilitates effective flow of air through the housing 2 over and through the heat exchanger 5 and the blower and motor assembly 6 since the path of air flow is vertical within the housing 2, from the bottom end 25 to the top end 24.

In one embodiment, also known as a pull-through arrangement, the heat exchanger 5 is positioned within the housing 2 adjacent to the air filter 4 and opposite the air intake opening 3 across the air filter 4, and the blower and motor assembly 6 is positioned within the housing 2 between the heat exchanger 5 and the air discharge opening 7. In other words the blower and motor assembly 6 is positioned vertically above the heat exchanger 5 within the housing 2.

In another embodiment, also known as a push-through arrangement, the relative position of the heat exchanger 5 and the blower and motor assembly 6 is reversed from the pull-through arrangement. Thus, the blower and motor assembly 6 is positioned within the housing 2 adjacent to the air filter 4 and opposite the air intake opening 3 across the housing 2, and the heat exchanger 5 is positioned within the housing 2 between the blower and motor assembly 6 and the air discharge opening 7. In other words, in the push-through arrangement the heat exchanger 5 is positioned vertically above the blower and motor assembly 6 within the housing 2. In any case, the air leaving the heat exchanger 5 is conditioned to provide cooling and dehumidification or heating depending on whether the system is an air conditioner or heat pump.

In the preferred embodiment of the present invention, the housing 2 additionally comprises an upper door 28 and a lower door 29, shown in FIGS. 1-2. In the pull-through arrangement, the upper door 28 is positioned adjacent to the blower and motor assembly 6, and the lower door 29 is positioned adjacent to the heat exchanger 5. In the push-through arrangement, the upper door 28 is positioned adjacent to the heat exchanger 5, and the lower door 29 is positioned adjacent to the blower and motor assembly 6. The upper and lower door 29 allow access to the heat exchanger 5 and the blower and motor assembly 6, in addition to any electrical components within the housing 2 which may require maintenance. The upper door 28 and the lower door 29 are preferably hingedly connected to the housing 2 by at least one hinge, and additionally at least one latch may be utilized to secure the upper door 28 and the lower door 29 in a closed position.

A secondary focus of the present invention is having various arrangements for the heat exchanger 5. In an A-coil 51 embodiment shown in FIGS. 2-4, the heat exchanger 5 is triangular in shape.

Referring to FIGS. 7-9, in a parallel coil embodiment, the heat exchanger 5 comprises a first coil panel 52 and a second coil panel 53. The first coil panel 52 and the second coil panel 53 are oriented parallel to each other, and are positioned vertically offset from each other within the housing 2. Additionally, the first coil panel 52 and the second coil panel 53 are angled relative to the central axis 26 of the housing 2, such that a vector normal to the first coil panel 52 and second coil panel 53 is angled relative to the central axis 26. The parallel coil embodiment is designed to make the air handling unit 1 more compact than the unit with the A-coil 51. In a circular coil 54 embodiment shown in FIGS. 10-12, the heat exchanger 5 is cylindrical, with an axis 55 of the heat exchanger 5 being oriented vertically and parallel to the central axis 26 of the housing 2. The axis of the heat exchanger 5 is preferably coincident with the central axis 26 of the housing 2, though in alternate circular coil 54 embodiments the axis 55 of the heat exchanger 5 may be offset from the central axis 26 of the housing 2.

In the circular coil 54 embodiment, the heat exchanger 5 comprises a vertical gap 56. The vertical gap 56 is oriented parallel to the axis of the heat exchanger 5, and traverses through a perimeter of the heat exchanger 5 into an interior of the heat exchanger 5. The vertical gap 56 preferably vertically traverses the height of the heat exchanger 5.

A drip tray 10 is also comprised in the preferred embodiment of the present invention. The drip tray 10 is positioned beneath the heat exchanger 5 in order to catch any condensation that may drop off the heat exchanger 5, and should be removable. In the parallel coil embodiment, a first drip tray 10 is positioned beneath the first coil panel 52, and a second drip dray is positioned beneath the second coil panel 53.

A lower shelf 11 is additionally positioned within the housing 2 above the heat exchanger 5 (in the pull-through arrangement), approximately halfway up the interior of the housing 2, between the heat exchanger 5 and the blower and motor assembly 6. The lower shelf 11 is preferably perimetrically connected to the inner shell 22 of the housing 2. A plurality of electrical components are preferably mounted on the lower shelf 11, though any of the electrical components may be alternately positioned or mounted in any other location within or outside the housing 2 which facilitates the proper operation of the present invention. An upper shelf 12 is also positioned within the housing 2 between the blower and motor assembly 6 and the air discharge opening 7 as well as being perimetrically connected to the inner shell 22, sealing the output of the blower and motor assembly 6 (in the pull-through arrangement) to be directed fully through the air discharge plenum 9.

The plurality of electrical components comprise any necessary elements required for an air handling unit 1 to function properly. The plurality of electrical components may include, but are not limited to, such elements as relays, transformers, capacitors, switches, integrated circuit boards, defrost control boards, a wireless communication device, digital displays and other control elements. The plurality of electrical components are electrically or electronically connected to each other in whatever manner that is necessary or desired to provide adequate and proper electrical control of the present invention. The blower and motor assembly 6 is electrically and/or electronically connected to at least one of the plurality of electrical components in order to provide control of the blower and motor assembly 6.

As previously stated, the object of the present invention is to achieve higher energy efficiency with an air handling unit 1 that is capable of eliminating corner flow singularities and eddies to save energy. Referring to FIGS. 13-14, the corner singularities and eddies revealed by an interferogram shown and a numerical flow distribution of airflow in a rectangular shaped air handling unit 1 dissipate in form of heat within the air handler requiring more power input from the blower motor. Referring to FIGS. 15-16, with the absence of corners, the air being drawn through an air handling unit 1 with a shape of continuous curvature such as a circular or cylindrical shape of the present invention does not develop into corner flow singularities and eddies as shown in an interferogram and a numerical flow distribution indicating no dissipation of energy. However, there is concentric flow recirculation or eddies in the cylindrical air handler. But these flow recirculation or eddies are weakened or suppressed by the presence of the heat exchanger 5 installed in the core of the air handling unit 1 as validated by a hotwire smoke visualization.

The dissipated or lost energy in rectangular air handler must be replenished by motor power if the flow rate is to be maintained, in the same way, as energy must be provided to overcome friction. Therefore, more energy will be used by the motor to accomplish same task in rectangular than in air handling unit 1 of continuous curvature such as a circular or cylindrical shape of this invention. Without the excess energy as described above, an air handling unit 1 with a shape of continuous curvature such as a circular or cylindrical will have higher energy efficiency ratio (EER) as a result of energy saved from reduction in motor power consumption, as compared to a similar rectangular air handling unit 1.

Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

What is claimed is:
 1. An air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements comprises: a housing; an air intake opening; an air filter; a heat exchanger; a blower and motor assembly; an air discharge opening; the housing comprises a top end and a bottom end positioned vertically opposite each other along the housing, wherein a central axis of the housing is oriented vertically; a cross-sectional profile of the housing being of continuous curvature; the air intake opening traversing through the housing at the bottom end; the air filter being positioned within the housing adjacent to the air intake opening; the heat exchanger and the blower and motor assembly being positioned vertically adjacent to each other within the housing; and the air discharge opening traversing through the housing at the top end.
 2. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the cross-sectional profile being circular, wherein the housing is cylindrical.
 3. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: an air discharge plenum; the air discharge plenum being adjacently connected to the top end of the housing; the air discharge plenum traversing through the top end of the housing; and the air discharge opening traversing through the air discharge plenum.
 4. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the heat exchanger being positioned within the housing adjacent to the air intake opening; the filter being positioned adjacent to the air intake opening opposite the heat exchanger; and the blower and motor assembly being positioned within the housing between the heat exchanger and the air discharge opening.
 5. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the blower and motor assembly being positioned within the housing adjacent to the air intake opening and opposite the air filter; and the heat exchanger being positioned within the housing between the blower and motor assembly and the air discharge opening.
 6. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the air intake opening traversing through the bottom end of the housing.
 7. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the heat exchanger being triangular in shape.
 8. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the heat exchanger comprises a first coil panel and a second coil panel; the first coil panel and the second coil panel being oriented parallel to each other; and the first coil panel and the second coil panel being positioned vertically offset from each other within the housing.
 9. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the heat exchanger being cylindrical; the heat exchanger comprises a vertical gap; an axis of the heat exchanger being oriented vertically; the vertical gap being oriented parallel to the axis of the heat exchanger; and the vertical gap laterally traversing through a perimeter of the heat exchanger into an interior of the heat exchanger.
 10. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: a drip tray; and the drip tray being positioned beneath the heat exchanger.
 11. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the housing further comprises an upper door and a lower door; the upper door being positioned adjacent to the blower and motor assembly; and the lower door being positioned adjacent to the heat exchanger.
 12. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the housing further comprises an upper door and a lower door; the upper door being positioned adjacent to the heat exchanger; and the lower door being positioned adjacent to the blower and motor assembly.
 13. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: an outer top cover; an air discharge plenum; the outer top cover being positioned concentric to the housing; the outer top cover being connected to the top end of the housing; and the air discharge plenum traversing through the outer top cover.
 14. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: the housing further comprises an outer shell and an inner shell; and the outer shell being concentrically positioned around the inner shell.
 15. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 14 comprises: the housing further comprises an insulation shell; and the insulation shell being positioned between the outer shell and the inner shell.
 16. The air handling unit that eliminates corner singularities and eddies for high energy efficiency and its evaporator heat exchanger coil arrangements as claimed in claim 1 comprises: an air filter compartment; the air filter compartment being positioned within the housing adjacent to the air intake opening; and the air filter being removably positioned within the air filter compartment. 